Multilayer electronic component

ABSTRACT

A multilayer electronic component include a first non-conductive resin layer, extending between a conductive resin layer and an electrode layer of a first external electrode, and a second non-conductive resin layer extending between a conductive resin layer and an electrode layer of a second external electrode. The first non-conductive layer and the second non-conductive layer may be spaced apart from each other to suppress arc discharge and to improve bending strength.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is the continuation application of U.S. patentapplication Ser. No. 16/857,264 filed on Apr. 24, 2020, which claims thebenefit of priority to Korean Patent Application No. 10-2019-0169536filed on Dec. 18, 2019 in the Korean Intellectual Property Office, theentire disclosure of which is incorporated herein by reference.

BACKGROUND 1. Field

The present disclosure relates to a multilayer electronic component.

2. Description of Related Art

A multilayer ceramic capacitor (MLCC), a type of multilayer electroniccomponent, may be a chip type capacitor mounted on a printed circuitboard of various electronic products such as imaging devices includingliquid crystal displays (LCDs), plasma display panels (PDPs), and thelike, and computers, smartphones, mobile phones, and the like, servingto charge or discharge electricity therein or therefrom.

Such multilayer ceramic capacitors may be used as components of variouselectronic devices due to their relatively small size, relatively highcapacitance, and relative ease of mounting. As various electronicdevices such as computers, mobile devices, or the like are miniaturizedand increased in terms of output, demand for miniaturization and highcapacitance of multilayer ceramic capacitors is increasing.

In addition, as recent interest in vehicle electric/electroniccomponents has increased, multilayer ceramic capacitors have also cometo require relatively high reliability and strength characteristics tobe used in vehicle or infotainment systems.

In order to secure high-reliability and high-strength characteristics, amethod of changing a conventional external electrode, including anelectrode layer, to have a double-layer structure including an electrodelayer and a conductive resin layer has been proposed.

In the double-layer structure including the electrode layer and theconductive resin layer, a resin composition, including a conductivematerial, is applied onto the electrode layer to absorb external impactsand to prevent permeation of plating liquid. As a result, reliabilitymay be improved.

However, since the standards for high reliability and high strengthcharacteristics required by the industry are increasing, there is demandfor a method of further improving high reliability and high strengthcharacteristics.

In addition, since a case, in which a multilayer ceramic capacitor isused under a high voltage, is increasing, there is a need for a methodof preventing an arc discharge from occurring between ends of bandportions of an external electrode.

SUMMARY

An aspect of the present disclosure is to provide a multilayerelectronic component, capable of suppressing arc discharge.

Another aspect of the present disclosure is to provide a multilayerelectronic component having improved bending strength characteristics.

Another aspect of the present disclosure is to provide a multilayerelectronic component having improved heat resistance.

Another aspect of the present disclosure is to provide a multilayerelectronic component having improved moisture resistance reliability.

Another aspect of the present disclosure is to provide a multilayerelectronic component having low equivalent series resistance (ESR)achieved by improving electrical connectivity between an electrode layerand a conductive resin layer.

However, the objects of the present disclosure are not limited to theabove description, and will be more easily understood in the process ofdescribing specific embodiments of the present disclosure.

According to an aspect of the present disclosure, a multilayerelectronic component includes a body including dielectric layers, andfirst and second internal electrodes alternately stacked with respectivedielectric layers interposed therebetween, and having first and secondsurfaces opposing each other in a stacking direction, third and fourthsurfaces connected to the first and second surfaces and opposing eachother, and fifth and sixth surfaces connected to the first to fourthsurfaces and opposing each other, a first external electrode including afirst electrode layer connected to the first internal electrode and afirst conductive resin layer disposed on the first electrode layer, andhaving a first connection portion disposed on the third surface of thebody and a first band portion extending from the first connectionportion along a portion of each of the first, second, fifth, and sixthsurfaces, a second external electrode including a second electrode layerconnected to the second internal electrode and a second conductive resinlayer disposed on the second electrode layer, and having a secondconnection portion disposed on the fourth surface of the body and asecond band portion extending from the second connection portion along aportion of each of the first, second, fifth, and sixth surfaces, andfirst and second non-conductive resin layers disposed on the first,second, fifth, and sixth surfaces and spaced apart from each other. Thefirst non-conductive resin layer extends between the first conductiveresin layer and the first electrode layer of the first band portion, andthe second non-conductive resin layer extends between the secondconductive resin layer and the second electrode layer of the second bandportion.

According to another aspect of the present disclosure, a multilayerelectronic component includes a body including dielectric layers, andfirst and second internal electrodes alternately stacked with respectivedielectric layers interposed therebetween, and having first and secondsurfaces opposing each other in a stacking direction, third and fourthsurfaces connected to the first and second surfaces and opposing eachother, and fifth and sixth surfaces connected to the first to fourthsurfaces and opposing each other, a first external electrode including afirst electrode layer connected to the first internal electrode and afirst conductive resin layer disposed on the first electrode layer, asecond external electrode including a second electrode layer connectedto the second internal electrode and a second conductive resin layerdisposed on the second electrode layer, and first and secondnon-conductive resin layers disposed on the first, second, fifth, andsixth surfaces and spaced apart from each other. The firstnon-conductive resin layer extends between the first conductive resinlayer and the first electrode layer, and the second non-conductive resinlayer extends between the second conductive resin layer and the secondelectrode layer. The first non-conductive resin layer includes one ormore first openings through which a portion of the first electrode layeris exposed to the first conductive resin layer, and the secondnon-conductive resin layer includes one or more second openings throughwhich a portion of the second electrode layer is exposed to the secondconductive resin layer.

BRIEF DESCRIPTION OF DRAWINGS

The above and other aspects, features, and advantages of the presentdisclosure will be more clearly understood from the following detaileddescription, taken in conjunction with the accompanying drawings.

FIG. 1 is a schematic perspective view of a multilayer electroniccomponent according to an exemplary embodiment of the presentdisclosure.

FIG. 2 is a cross-sectional view taken along line I-I′ in FIG. 1 .

FIG. 3 is a schematic exploded perspective view of a body in whichdielectric layers and internal electrodes are laminated according to anexemplary embodiment of the present disclosure.

FIG. 4 is an enlarged view of region P in FIG. 2 .

FIG. 5 illustrates a bending test method.

FIG. 6 is a graph illustrating evaluation of bending strength of amultilayer electronic component depending on whether a non-conductiveresin of the present disclosure is applied, which shows a bending testresult obtained by the test method of FIG. 5 .

FIG. 7 is a graph illustrating evaluation of ESR after a cycle TC, inwhich a temperature, changed from −55° C. to 150° C., was repeated 200times on twenty samples of Test No. 5 of Table 1.

FIG. 8 illustrates an arc discharge occurrence voltage repeatedlymeasured five times for ten sample chips (#1 to #10) of the ComparativeExample in which a non-conductive resin layer is not disposed.

FIG. 9 illustrates an arc discharge occurrence voltage repeatedlymeasured five times for ten sample chips (#1 to #10) of the InventiveExample in which a non-conductive resin layer is disposed according toan exemplary embodiment of the present disclosure.

FIG. 10 is a schematic perspective view of a multilayer electroniccomponent according to an exemplary embodiment of the presentdisclosure.

FIG. 11 is a cross-sectional view taken along line II-II′ in FIG. 11 .

DETAILED DESCRIPTION

Hereinafter, embodiments of the present disclosure will be describedwith reference to specific embodiments and the accompanying drawings.However, embodiments of the present disclosure may be modified to havevarious other forms, and the scope of the present disclosure is notlimited to the embodiments described below. Further, embodiments of thepresent disclosure may be provided for a more complete description ofthe present disclosure to the ordinarily skilled artisan. Therefore,shapes and sizes of the elements in the drawings may be exaggerated forclarity of description, and the elements denoted by the same referencenumerals in the drawings may be the same elements.

In the drawings, portions not related to the description will be omittedfor clarification of the present disclosure, and a thickness may beenlarged to clearly show layers and regions. The same reference numeralswill be used to designate the same components in the same referencenumerals. Further, throughout the specification, when an element isreferred to as “comprising” or “including” an element, it means that theelement may further include other elements as well, without departingfrom the other elements, unless specifically stated otherwise.

In the drawing, an X direction may be defined as a second direction, anL direction, or a longitudinal direction, a Y direction may be definedas a third direction, a W direction, or a width direction, and a Zdirection may be defined as a first direction, a stacking direction, a Tdirection, or a thickness direction.

Multilayer Electronic Component

FIG. 1 is a schematic perspective view of a multilayer electroniccomponent according to an exemplary embodiment of the presentdisclosure.

FIG. 2 is a cross-sectional view taken along line I-I′ in FIG. 1 .

FIG. 3 is a schematic exploded perspective view of a body in whichdielectric layers and internal electrodes are laminated according to anexemplary embodiment.

FIG. 4 is an enlarged view of region P in FIG. 2 .

Hereinafter, a multilayer electronic component 100 according to anexemplary embodiment will be described with reference to FIGS. 1 to 4 .

A multilayer electronic component 100 according to an exemplaryembodiment may include a body 110 including dielectric layers 111, andfirst and second internal electrodes 121 and 122 alternately laminatedwith respective dielectric layers interposed therebetween, and havingfirst and second surfaces 1 and 2 opposing each other in a stackingdirection (e.g., a Z direction), third and fourth surfaces 3 and 4connected to the first and second surfaces 1 and 2 and opposing eachother, and fifth and sixth surfaces 5 and 6 connected to the first tofourth surfaces 1, 2, 3, and 4 and opposing each other, a first externalelectrode 131 including a first electrode layer 131 a connected to thefirst internal electrode 121 and a first conductive resin layer 131 bdisposed on the first electrode layer 131 a, and having a firstconnection portion A1 disposed on the third surface 3 of the body 110and a first band portion B1 extending from the first connection portionA1 to a portion of each of the first, second, fifth, and sixth surfaces1, 2, 5, and 6, a second external electrode 132 including a secondelectrode layer 132 a connected to the second internal electrode 122 anda second conductive resin layer 132 b disposed on the second electrodelayer 132 a, and having a second connection portion A2 disposed on thefourth surface 4 of the body 110 and a second band portion B2 extendingfrom the second connection portion A2 to a portion of each of the first,second, fifth, and sixth surfaces 1, 2, 5, and 6, first and secondnon-conductive resin layers 141 and 142 disposed on the first, second,fifth, and sixth surfaces 1, 2, 5, and 6 and spaced apart from eachother. The first non-conductive resin layer 141 is disposed to extendbetween the first conductive resin layer 131 b and the first electrodelayer 131 a of the first band portion B1, and the second non-conductiveresin layer 142 is disposed to extend between the second conductiveresin layer 132 b and the second electrode layer 132 a of the secondband portion B2.

In the body 110, the dielectric layers 111 and the internal electrodes121 and 122 are alternately laminated.

The body 110 is not limited in shape, but may have a hexahedral shape ora shape similar thereto. Due to shrinkage of ceramic powder particlesincluded in the body 110 during sintering, the body 110 may have asubstantially hexahedral shape rather than a hexahedral shape havingcomplete straight lines.

The body 110 may have the first and second surfaces 1 and 2 opposingeach other in a thickness direction (e.g., a Z direction), the third andfourth surfaces 3 and 4 connected to the first and second surfaces 1 and2 and opposing each other in a length direction (e.g., an X direction),and the fifth and sixth surfaces 5 and 6 connected to the first andsecond surfaces 1 and 2 and as well as to the third and fourth surfaces3 and 4 and opposing each other in a width direction (e.g., an Ydirection).

The plurality of dielectric layers 111, constituting the body 110, is ina sintered state and may be integrated with each other such thatboundaries therebetween may not be readily apparent without using ascanning electron microscope (SEM).

According to an exemplary embodiment, a raw material forming thedielectric layer 111 is not limited as long as sufficient capacitancemay be obtained. For example, the raw material forming the dielectriclayer 111 a may a barium titanate-based material, a lead compositeperovskite-based material, a strontium titanate-based material, or thelike. The barium titanate-based material may include BaTiO₃-basedceramic powder particles. The BaTiO₃-based ceramic powder may be, forexample, (Ba_(1-x)Ca_(x))TiO₃, Ba(Ti_(1-y)Ca_(y))O₃,(Ba_(1-x)Ca_(x))(Ti_(1-y)Zr_(y))O₃, Ba(Ti_(1-y)Zr_(y))O₃, and the like,prepared by partially employing calcium (Ca), zirconium (Zr), and thelike, in BaTiO₃.

Various ceramic additives, organic solvents, plasticizers, binders,dispersants, or the like, may be added to the powder particles of bariumtitanate (BaTiO₃), or the like, according to the purpose of the presentdisclosure, as the material for forming the dielectric layer 111. Theceramic additive may include transition metal oxides or carbides, rareearth elements, magnesium (Mg), aluminum (Al), or the like

The body 110 may have a capacitance forming portion disposed in the body110 and including the first and second internal electrode layers 121 and122, disposed to oppose each other with the dielectric layer 111interposed therebetween, to form capacitance, and upper and lowerprotective layers 112 and 113 disposed above and below the capacitanceforming portion.

The capacitance forming portion may contribute to capacitance formationof a capacitor, and may be formed by repeatedly laminating the pluralityof first and second internal electrode layers 121 and 122 with thedielectric layer 111 interposed therebetween.

The upper protective layer 112 and the lower protective layer 113 may beformed by laminating a single dielectric layer or two or more dielectriclayers on upper and lower surfaces of the capacitance forming portion,respectively, in the vertical direction, and may basically play a rolein preventing damage to the internal electrodes due to physical orchemical stress.

The upper protective layer 112 and the lower protective layer 113 maynot include an internal electrode, and may include the same material asthe dielectric layer 111.

The internal electrodes 121 and 122 may be disposed to oppose each otherwith the dielectric layer 111 interposed therebetween.

The internal electrodes 121 and 122 may include first and secondinternal electrodes 121 and 122 alternately disposed to oppose eachother with respective dielectric layers interposed therebetween.

The first and second internal electrode layers 121 and 122 may beexposed to the third and fourth surfaces 3 and 4 of the body 110,respectively.

Referring to FIG. 2 , the first internal electrode 121 may be spacedapart from the fourth surface 4 and may be exposed through the thirdsurface 3, and the second internal electrode 122 may be spaced apartfrom the third surface 3 and may be exposed through the fourth side 4.The first external electrode 131 may be disposed on the third surface 3of the body 110 to be connected to the first internal electrode 121, andthe second external electrode 132 may be disposed on the fourth surface4 of the body 110 to be connected to the internal electrode 122.

For example, the first internal electrode 121 is not connected to thesecond external electrode 132 and is connected to the first externalelectrode 131, and the second internal electrode 122 is not connected tothe first external electrode 131 and is connected to the second externalelectrode 132. Accordingly, the first internal electrode 121 is spacedapart from the fourth surface 4 by a predetermined distance, and thesecond internal electrode 122 is spaced apart from the third surface 3by a predetermined distance.

The first and second internal electrode layers 121 and 122 may beelectrically isolated from each other by the dielectric layer 111disposed therebetween.

Referring to FIG. 3 , the body 110 may be formed by alternatelylaminating a dielectric layer 111, on which a first internal electrode121 is printed, and a dielectric layer 111, on which a second internalelectrode 122 is printed, in a thickness direction (e.g., Z direction)and sintering the laminated dielectric layers 111.

A material of the internal electrodes 121 and 122 is not necessarilylimited, and may be a material having improved electrical conductivity.For example, the internal electrodes 121 and 122 may be formed byprinting an internal electrode conductive paste, including at least oneof nickel (Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au),platinum (Pt), tin (Sn), and tungsten (W), titanium (Ti), and alloysthereof, on a ceramic green sheet.

A method of printing the internal electrode conductive paste may be ascreen-printing method or a gravure printing method, but is not limitedthereto.

The external electrodes 131 and 132 are disposed on the body 110 andinclude electrode layers 131 a and 132 a and conductive resin layers 131b and 132 b.

The external electrodes 131 and 132 may include first and secondexternal electrodes 131 and 132, respectively connected to the first andsecond internal electrodes 121 and 122.

The first external electrode 131 may include a first electrode layer 131a and a first conductive resin layer 131 b, and the second externalelectrode 132 may include a second electrode layer 132 a and a secondconductive resin layer 132 b.

A region of the first external electrode 131 may be divided depending ona location thereof with reference to FIG. 2 . The first externalelectrode 131 may have a first connection portion A1, disposed on thethird surface 3 of the body 110, and a band portion B1 extending fromthe first connection portion A1 to a portion of the first, second,fifth, and sixth portions 1, 2, 5, and 6.

In addition, a region between the first connection portion A1 and thefirst band portion B1 may be defined as a first corner portion C1. Forexample, a portion of the first external electrode 131, disposed on thethird surface 3 of the body 110, may referred to as a first connectionportion A1, a portion of the first external electrode 131, disposed onthe first, second, fifth, and sixth surfaces of the body 110, may bereferred to as a first band portion B1, and a region of the firstexternal electrode 131, disposed between the first connection portion A1and the first band portion B1 may be referred to as a first cornerportion C1.

A region of the second external electrode 131 may be divided dependingon a location thereof. The second external electrode 132 has a secondconnection portion A2, disposed on the fourth surface 4 of the body 110,and a second band portion B2 extending from the second connectionportion A2 to a portion of the first, second, fifth, and sixth surfaces1, 2, 5, and 6.

In addition, a region between the second connection portion A2 and thesecond band portion B2 may be defined as a second corner portion C2. Forexample, a portion of the second external electrode 132, disposed on thefourth surface 4 of the body 110, may referred to as a second connectionportion A1, a portion of the second external electrode 131, disposed onthe first, second, fifth, and sixth surfaces of the body 110, may bereferred to as a second band portion B2, and a region of the secondexternal electrode 132, disposed between the second connection portionA2 and the second band portion B2 may be referred to as a second cornerportion C2.

According to an exemplary embodiment of the present disclosure, inregions of the first and second connection portions A1 and A2corresponding to the third and fourth surfaces 3, 4 of the body 110, aportion of the first electrode layer 131 a may be in contact with firstconductive resin layer 131 b through an opening of the firstnon-conductive resin layer 141, and a portion of the second electrodelayer 132 a may be in contact with the second conductive resin layer 132b through an opening of the second non-conductive resin layer 142.

The external electrodes 131 and 132 may be formed of any material, aslong as it has electrical conductivity, such as a metal. A detailedmaterial of the external electrodes 131 and 132 may be selected inconsideration of electrical characteristics, structural stability, andthe like.

For example, each of the first and second electrode layers 131 and 132may include a conductive meal and glass.

A conductive metal used for the electrode layers 131 a and 132 a is notnecessarily limited as long as it may be electrically connected to theinternal electrode to form capacitance. The conductive material may be,for example, at least one selected from the group consisting of nickel(Ni), copper (Cu), palladium (Pd), silver (Ag), gold (Au), platinum(Pt), tin (Sn), tungsten (W), titanium (Ti), and alloys thereof.

The electrode layers 131 a and 132 a may be formed by applying aconductive paste, prepared by adding a glass frit to conductive metalpowder particles, and then sintering the conductive paste.

When the first and second electrode layers 131 a and 132 a include aconductive metal and glass, each of the corner portions C1 and C2,regions between the connection portions A1 and A2 and the band portionsB1 and B2, may be formed to have a low thickness, or lifting may occurbetween ends of the bands B1 and B2 and the body 110 to deterioratemoisture resistance reliability. Accordingly, when the first and secondelectrode layers 131 and 132 include a conductive metal and glass, aneffect of improving moisture resistance reliability may be improved.

The first and second electrode layers 131 a and 132 a may be formed bymeans of atomic layer deposition (ALD), molecular layer deposition(MLD), chemical vapor deposition (CVD), sputtering, or the like.

The first and second electrode layers 131 a and 132 a may be formed bytransferring a sheet, including a conductive metal, to the body 110.

Each of the conductive resin layers 131 b and 132 b may include aconductive metal and a base resin.

The conductive metal, included in each of the conductive resin layers131 b and 132 b, serve to electrically connect the conductive resinlayers 131 b and 132 b to the electrode layers 131 a and 132 a.

The conductive metal, included in each of the electrode layers 131 a and132 a, is not necessarily limited as long as it may be electricallyconnected to the internal electrode to form capacitance. The conductivematerial may be, for example, at least one selected from the groupconsisting of nickel (Ni), copper (Cu), palladium (Pd), silver (Ag),gold (Au), platinum (Pt), tin (Sn), tungsten (W), titanium (Ti), andalloys thereof.

The conductive metal, included in the conductive resin layers 131 b and132 b, may include at least one of spherical powder particles and flakepowder particles. For example, the conductive metal may include onlyflake powder particles, or spherical powder particles, or a mixture offlake powder particles and spherical powder particles.

The spherical powder particles may have an incompletely spherical shapeand may have, for example, a shape in which a ratio of a length of amajor axis to a length of a minor axis (the major axis/the minor axis)is 1.45 or less.

The flake powder particles refer to powder particles, each having a flatand elongated shape, and is not limited to a specific shape and, forexample, a ratio of a length of a major axis and a length of a minoraxis (the major axis/the minor axis) may be 1.95 or more.

The lengths of the major axes and the minor axes of the spherical powderparticles and the flake powder particles may be measured from an imageobtained by scanning a cross section (an L-T cross section), taken froma central portion of a multilayer electronic component in a width (Y)direction, in X and Z directions with a scanning electron microscope(SEM).

The base resin, included in the conductive resin layers 131 b and 132 b,serves to secure adhesion and to absorb impacts.

The base resin, included in the conductive resin layers 131 b and 132 b,is not necessarily limited as long as it has adhesion and impactabsorption and is mixed with conductive metal powder particles toprepare a paste and may include, for example, an epoxy-based resin.

In addition, the conductive resin layer may include a plurality of metalparticles, an intermetallic compound, and a base resin.

According to the present disclosure, the non-conductive resin layer 140,which includes the first and second non-conductive resin layers 141 and142, may be disposed to extend between the electrode layers 131 a and132 a and the conductive resin layers 131 b and 132 b, or a plurality ofisland-shaped adhesive portions 151 and 152 may be disposed on the firstelectrode layer 131 a of the first connection portion A1 and the secondelectrode layer 132 a of the second connection portion A2. Therefore, acontact area between the electrode layers 131 a and 132 a and theconductive resin layers 131 b and 132 b may be reduced. As a result,electrical connectivity between the electrode layers 131 a and 132 a andthe conductive resin layers 131 b and 132 b may be deteriorated.

However, according to an exemplary embodiment, when each of theconductive resin layers 131 b and 132 b includes a plurality of metalparticles, an intermetallic compound, and a base resin, stableelectrical connectivity may be secured.

The intermetallic compound may serve to connect a plurality of metalparticles to improve electrical connectivity, and may serve to surroundand connect the plurality of metal particles to each other.

In this case, the intermetallic compound may include a metal having amelting point lower than a curing temperature of a base resin.

For example, since the intermetallic compound includes a metal having amelting point lower than the curing temperature of the base resin, themetal having a melting point lower than the curing temperature of thebase resin is melted during drying and curing processes and forms anintermetallic compound with a portion of the metal particles to surroundthe metal particles. In this case, the intermetallic compound mayinclude, in detail, a metal having a low melting point of 300{acute over(Ε)} or less.

For example, the intermetallic compound may include tin (Sn) having amelting point of 213{acute over (Ε)} to 220{acute over (Ε)}. The tin(Sn) is melted during the drying and curing process, and the melted Snwets high-melting metal particles having a high melting point such asAg, Ni, or Cu due to capillarity and reacts with a portion of Ag, Ni, orCu metal particles to form an intermetallic compound such as Ag₃Sn,Ni₃Sn₄, Cu₆Sn₅, Cu₃Sn, or the like. Ag, Ni or Cu, not participating inthe reaction, remains in the form of metal particles.

Thus, the plurality of metal particles may include at least one of Ag,Ni, and Cu, and the intermetallic compound may include at least one ofAg₃Sn, Ni₃Sn₄, Cu₆Sn₅, and Cu₃Sn.

The external electrodes 131 and 132 may further include plating layers,not illustrated, disposed on the conductive resin layers 131 b and 132 bto improve mounting characteristics.

For example, the plating layer may be a Ni plating layer or a Sn platinglayer, may have a form in which a Ni plating layer and a Sn platinglayer are sequentially formed on the conductive resin layers 131 b and132 b), or may include a plurality of Ni plating layers and/or aplurality Sn plating layers.

The non-conductive resin layer 140 includes first and secondnon-conductive resin layers 141 and 142.

The first and second non-conductive resin layers 141 and 142 aredisposed on the first, second, fifth, and sixth surfaces 1, 2, 5, and 6of the body 110 and are spaced apart from each other.

The first non-conductive resin layer 141 is disposed to extend betweenthe first conductive resin layer 131 b and the first electrode layer 131a of the first band portion B1, and the second non-conductive resinlayer 142 is disposed to extend between the second conductive resinlayer 132 b and the second electrode layer 132 a of the second bandportion B2.

The non-conductive resin layer 140 serves to prevent stress, generatedwhen a substrate is deformed by thermal and physical impacts while themultilayer electronic component 100 is mounted on the substrate, frompropagating to the body 110 and to prevent cracking.

In addition, the non-conductive resin layer 140 blocks a moisturepermeation path to improve moisture resistance reliability.

The base resin, included in the conductive resin layers 131 b and 132 b,also plays a role in absorbing impacts, but the role of the base resinis limited because the first resin layer 131 b and the second conductiveresin layer 132 b should be disposed to be insulated.

In addition, when lengths of the first and second conductive resinlayers 131 b and 132 b are increased to enhance bending stress, ashort-circuit may occur between the first and second conductive resinlayers 131 b and 132 b, and arc discharge may occur between ends of bandportions of the first and second conductive resin layers 131 b and 132 bunder a high voltage.

Meanwhile, since the non-conductive resin layer 140 is non-conductive, ashort-circuit does not occur even when a gap G between the first resinlayer 141 and the second resin layer 142 is small. Therefore, the gap Gmay be sufficiently reduced to efficiently absorb impacts and suppresspropagation of stress. In addition, the gap G may be sufficientlyreduced to suppress occurrence of the arc discharge.

The non-conductive resin layer 140, disposed to be in contact with asurface of the body 110, may seal fine pore or cracking of the body 110to prevent moisture from permeating into the body 110 through amexternal surface of the body 110.

The first non-conductive resin layer 141 extends between the firstconductive resin layer 131 b and the first electrode layer 131 a of thefirst band portion B1 to prevent stress from propagating to the body 110and to prevent cracking.

In addition, the first non-conductive resin layer 141 suppresses liftingbetween an end of the first electrode layer 131 a, disposed in the firstband portion B1, and the body 110 to improve moisture resistancereliability.

The second non-conductive resin layer 142 extends between the secondconductive resin layer 132 b and the second electrode layer 132 a of thesecond band portion B2 to prevent the stress from propagating to thebody 110 and to prevent cracking.

In addition, the second non-conductive resin layer 142 suppresseslifting between an end of the second electrode layer 132 a, disposed inthe second band portion B2, and the body 110 to improve moistureresistance reliability.

When a direction, in which the third surface 3 and the fourth surface 4of the body 110 oppose each other, is defined as a length direction (anX direction) of the body 110, the first non-conductive resin layer 141and the second non-conductive resin layer 142 may be spaced apart fromeach other with a central portion of the body 110 in the lengthdirection (the X direction) interposed therebetween. Such a dispositionof the first non-conductive resin layer 141 and the secondnon-conductive resin layer 142 may allow an arc discharge suppressioneffect to be significantly improved.

A gap G between the first non-conductive resin layer 141 and the secondnon-conductive resin layer 142 may be 30% or less of the length of thebody 110. When the gap G is greater than 30% of the length of the body110, an arc discharge suppression effect or a bending strengthimprovement effect may be insufficient. The length of the body 110 maybe a distance between the third and fourth surfaces of the body 110 inthe length direction.

A gap G between the first non-conductive resin layer 141 and the secondnon-conductive resin layer 142 may be less than a gap between the firstconductive resin layer 131 b and the second conductive resin layer 132b. For example, the sum of a length B1 b of the band portion B1 of thefirst conductive resin layer 131 b, a length of the band portion B2 ofthe second conductive resin layer 132 b, and the gap G between the firstnon-conductive resin layer 141 and the second non-conductive layer 142may be less than the length of the body 110. When the gap G between thefirst non-conductive resin layer 141 and the second non-conductive resinlayer 142 is greater than or equal to the gap between the firstconductive resin layer 131 b and the second conductive resin layer 132b, an arc discharge suppressing effect or a bending strength improvementeffect may be insufficient.

A lower limit of the gap G is not necessarily limited. However, when agap G between the first non-conductive resin layer 141 and the secondnon-conductive resin layer 142, disposed to be in contact with eachother, is zero, the stress is not dispersed, and thus, the bendingstrength improving effect may be insufficient. For example, as the firstnon-conductive resin layer 141 and the second non-conductive resin layer142 are spaced apart from each other, the stress may be dispersed toimprove the bending strength improvement effect.

FIG. 5 illustrates a bending test method.

FIG. 6 is a graph illustrating evaluation of bending strength of amultilayer electronic component depending on whether a non-conductiveresin 140 of the present disclosure is applied, which shows a bendingtest result obtained by the test method of FIG. 5 .

In FIG. 6 , Comparative Example is a multilayer electronic component towhich the non-conductive resin layer 140 is not applied, and InventiveExample is a multilayer electronic component to which the non-conductiveresin layer 140 is applied. Thirty samples were prepared for each ofComparative Example and Inventive Example.

Referring to FIG. 5 , while mounting a sample chip (MLCC) on a substrate(PCB) and pressing a surface opposing a mounting surface of the samplechip (MLCC) up to 6 mm, a peel-off point (in which an external electrodepeels off from a body) and a cracking occurrence point (in which thebody is cracked) are shown in FIG. 6 as piezo peak positions.

In Comparative Example, peel-off (an external electrode peels off from abody) or cracking (the body is cracked) occurred in all of the thirtysamples. Meanwhile, in the Inventive Example, it can be confirmed thatno defect was found in all of the thirty samples, and thus, bendingstrength can be guaranteed during a bending strength test of 6 mm.

The non-conductive resin layer 140 may be formed by forming first andsecond electrode layers 131 a and 132 a in a body 110 includingdielectric layers and internal electrodes, forming a non-conductiveresin layer on an exposed external surface of the body 110 and the firstand second electrode layers 131 a and 132 a, and removing anon-conductive resin layer formed on connection portions A1 and A2 ofthe first and second electrode layers 131 a and 132 a and anon-conductive resin layer formed in a central portion of the body 110in a length direction.

A method of removing the non-conductive resin layer 140 may be, forexample, laser processing, mechanical polishing, dry etching, wetetching, shadowing deposition using a tape protective layer, or thelike.

The non-conductive resin layer 140 may include a base resin.

The base resin, included in the non-conductive resin layer 140, is notnecessarily limited as long as it has adhesion and impact absorbingproperties and may be, for example, an epoxy-based resin.

The non-conductive resin layer 140 may include a base resin, and mayinclude one or more fillers among silica, alumina, glass, and zirconiumdioxide (ZrO₂).

Silica, alumina, glass, and zirconium dioxide (ZrO₂), used as fillers,serve to improve an application shape of the non-conductive resin layer140. In addition, silica, alumina, glass, and zirconium dioxide (ZrO₂)may also serve to improve heat resistance.

In this case, the content of a filler, included in the non-conductiveresin layer 140, is not necessarily limited and may be specificallydetermined in consideration of a type of the filler, type of a resin ofthe non-conductive resin layer, and an effect desired to be obtainedtherefrom.

As a detailed example, when a filler of the non-conductive resin layer140 is silica and a resin of the non-conductive resin layer 140 is anepoxy resin, the content of the filler included in the non-conductiveresin layer 140 may be 10% or more by volume, preferably, 20% or more byvolume, and more preferably, 40% or more by volume. Therefore, the firstnon-conductive resin layer 141 may include 10% or more by volume of afiller, and the second non-conductive resin layer 142 may include 10% ormore by volume of a filler.

Table 1 shows evaluation of heat resistance of a sample chip includingthe non-conductive resin layer 140 according to an example after thesample chip was manufactured while varying the content of a fillerincluded in the non-conductive resin layer 140. In the non-conductiveresin layer, silica was added to an epoxy resin as a filler. The contentof the filler to the entire non-conductive resin layer was representedby volume percent (vol %).

Heat resistance was evaluated by exposing sample chips at temperature of260° C. for 20 seconds and then checking the degree of deformation of anon-conductive resin layer after exposing the sample chips, as comparedwith a non-conductive resin layer before exposing the sample chips. InTable 1, X represents a case in which the degree of deformation was 30%or more, Δ represents a case in which the degree of deformation was 10%or more to less than 30%, ○ represents a case in which the degree ofdeformation was less than 10%, and ⊚ represents a case in whichdeformation did not occur.

TABLE 1 Test No. Filler Content (vol %) Heat Resistance  1* 0 X  2* 5 X3 10 Δ 4 15 Δ 5 20 ◯ 6 25 ◯ 7 30 ◯ 8 35 ◯ 9 40 ⊚

As can be seen from Table 1, in the case of Test Nos. 1 and 2, thecontent of a filler is less than 10 volume percent and the heatresistance is deteriorated.

Test Nos. 3 to 9 were compared. When a filler included in thenon-conductive resin layer is silica and a resin included in thenon-conductive resin layer is an epoxy resin, the content of the fillermay be, preferably, 10% by volume in terms of heat resistance, may be,more preferably, 20% or more by volume, and may be, further morepreferably, 40% or more by volume.

FIG. 7 is a graph illustrating evaluation of ESR after a cycle TC, inwhich a temperature changed from −55° C. to 150° C., was repeated 200times on twenty sample chips (sample Nos. 1 to 20) of Test No. 5 inTable 1. As can be seen from FIG. 7 , ESR before and after TC werealmost similar to each other and heat resistance was improved.

FIG. 8 illustrates an arc discharge occurrence voltage repeatedlymeasured five times for ten sample chips (#1 to #10) of ComparativeExample in which a non-conductive resin layer 140 is not disposed.

FIG. 9 illustrates an arc discharge occurrence voltage repeatedlymeasured five times for ten sample chips (#1 to #10) of the InventiveExample in which a non-conductive resin layer 140 is disposed, accordingto an exemplary embodiment.

As can be seen from FIG. 8 , since there were four cases in which arcdischarge occurred at 2 kV or less, an average value of the arcdischarge occurrence voltage was about 2.5 kV.

Meanwhile, as can be seen from FIG. 9 , in the case of InventiveExample, arc discharge did not occur at 2.2 kV or less in a total of 50tests. In addition, an average value of an arc discharge occurrencevoltage is was higher than that in Comparative Example and an arcdischarge suppression effect was improved.

The first non-conductive resin layer 141 is disposed to cover the firstelectrode layer 131 a of the first corner portion (C1), and the secondnon-conductive resin layer 142 is disposed to cover the second electrodelayer 132 a of the second corner portion C2.

When the electrode layers 131 a and 132 a includes a conductive metaland glass, the electrode layers 131 a and 132 a of the corner portionsC1 and C2, regions between the connection portions A1 and A2 and theband portions B1 and B2, are formed to have high thicknesses,respectively. The corner portions C1 and C2 serve as main moisturepermeation paths to deteriorate moisture resistance reliability.

Therefore, the non-conductive resin layer 140 may be disposed to coverthe electrode layers 131 a and 132 a of the corner portions C1 and C2.As a result, the moisture permeation paths may be blocked to improve themoisture resistance reliability.

In addition, the first non-conductive resin layer 141 is disposed toextend to a portion between the first conductive resin layer 131 b andthe first electrode layer 131 a of the first connection portion A1, andthe second non-conductive The resin layer 142 extends to a portionbetween the second conductive resin layer 132 b and the second electrodelayer 132 a of the second connection portion A2. As a result, themoisture permeation path may be more tightly blocked to further improvemoisture resistance reliability.

A length of each of the first conductive resin layer 131 b of the firstband portion B1 and the second conductive resin layer 132 b of thesecond band portion B2 may be 10 to 20% of a length of the body 110.

Referring to FIGS. 2 and 4 , a length of a body may refer to a distancebetween a third surface and a fourth surface of the body, a length ofthe first conductive resin layer 131 b of the first band portion B1 maybe a distance B1 b from the third surface of the body 110 to an end ofthe first conductive resin layer 131 b, and a length of the secondconductive resin layer 132 b of the second band portion B2 may be adistance from the fourth surface of the body 110 to an end of the secondconductive resin layer 132 b.

When the non-conductive resin layer 140 is not disposed, the length ofeach of the first conductive resin layer 131 b of the first band portionB1 and the second conductive resin layer 132 b of the second bandportion B2 should be maintained at a range of 20 to 30% of the length ofthe body 110 to secure bending strength.

Meanwhile, when the non-conductive resin layer 140 is disposed accordingto an exemplary embodiment, sufficient bending strength may be securedeven in the case in which the length of each of the first conductiveresin layer 131 b of the first band portion B1 and the second conductiveresin layer 132 b of the second band portion B2 is 10 to 20 percent ofthe length of the body 110. Thus, the arc discharge suppression effectmay be further improved.

In order to further improve the bending strength, the distance B1 b fromthe third surface of the body to the end of the first conductive resinlayer 131 b may be greater than the distance B1 a from the third surfaceof the body to the end of the first electrode layer 131 a. Similarly, adistance from the fourth surface of the body to the end of the secondconductive resin layer 132 b may be greater than a distance from thefourth surface of the body to the end of the second electrode layer 132a.

FIG. 10 is a schematic perspective view of a multilayer electroniccomponent according to an exemplary embodiment of the presentdisclosure.

FIG. 11 is a cross-sectional view taken along line II-II′ in FIG. 11 .

Hereinafter, a multilayer electronic component 100′ according to anotherexemplary embodiment will be described with reference to FIGS. 10 and 11. However, the same descriptions of the multilayer electronic component100′ as those of the multilayer electronic component 100 according to anexemplary embodiment will be omitted to avoid duplicate descriptions.

The multilayer electronic component 100′ according to another exemplaryembodiment may have a plurality of first and second island-shapedadhesive portions 151 and 152 on a first electrode layer 131 a of afirst connection portion A1 and a second electrode layer 132 a of asecond connection portion A2, respectively.

Referring to FIG. 11 , the plurality of first and second island-shapedadhesive portions 151 and 152 may be respectively arranged between afirst conductive resin layer 131 b and a first electrode layer 131 a ofthe first connection portion A1 and between a second conducive resinlayer 132 b and a second electrode layer 132 a of the second connectionportion A2.

That is, the first non-conductive resin layer 141 may include one ormore first openings through which a portion of the first electrode layer131 a is exposed to the first conductive resin layer 131 b, and thesecond non-conductive resin layer 142 may include one or more secondopenings through which a portion of the second electrode layer 132 a isexposed to the second conductive resin layer 132 b. The one or morefirst openings and the one or more second openings each may include aplurality of discrete openings spaced apart from one another.

The plurality of first and second island-shaped adhesive portions 151and 152 serve to improve adhesion between the electrode layers 131 a and132 a and the conductive resin layers 131 b and 132 b. As the adhesionbetween the electrode layers 131 a and 132 a and the conductive resinlayers 131 b and 132 b is improved, a defect such as electrode liftingmay be prevented.

Each of the plurality of first and second island-shaped adhesiveportions 151 and 152 may include a base resin.

The base resin, included in the plurality of first and secondisland-shaped adhesive portions 151 and 152, is not necessarily limitedas long as it has an adhesive property and impact absorption and may be,for example, an epoxy resin.

In addition, the plurality of first and second island-shaped adhesiveportions 151 and 152 may include a base resin, and may include at leastone of silica, alumina, glass, or zirconium dioxide (ZrO₂). Silica,alumina, glass, and zirconium dioxide (ZrO₂) serve to improve anapplying shape and to improve heat resistance.

The plurality of first and second island-shaped adhesive portions 151and 152 may be formed by forming first and second electrode layers 131 aand 132 a in a body 110 including dielectric layers and internalelectrodes, forming a non-conductive resin layers on an exposed externalsurfaces of the body 110 and the first and second electrode layers 131 aand 132 a, and removing only a portion of the non-conductive resin layer140 formed on the connection portions A1 and A2 of the first and secondelectrode layers 131 a and 132 a.

Therefore, the plurality of first and second island-shaped adhesiveportions 151 and 152 may be formed of the same material as the first andsecond non-conductive resin layers 140.

A collective area of the plurality of first island-shaped adhesiveportions 151 and a collective area of the plurality of secondisland-shaped adhesive portions 152 may be 20 to 40 percent of an areaof the first electrode layer 131 a of the first connection portion A1and an area of the second electrode layer 132 a of the second connectionportion A2, respectively.

Table 2 shows evaluation results of ESR and adhesion depending on aratio of an area S2 of the adhesive portion to an area S1 of theelectrode layer of the connection portion (S2/S1).

The adhesion was evaluated by measuring energy using a bond tester whena conductive resin layer is separated falls from an electrode layer. Ascompared with a case in which the area S2 of the adhesive portion is 0,Δ represents a case in which an adhesion improvement effect was lessthan 5%, ○ represents a case in which the adhesion improvement effectwas 5% or more to 20% or less, and ⊚ represents a case in which theadhesion improvement effect was 20% or more.

ESR evaluation was performed by measuring ESR of 100 samples at aself-resonant frequency using an LCR meter. In Table 2, Δ represents acase in which a coefficient of variation (CV) was more than or equal to10%, ○ represents a case in which the CV was 3% or more to less than10%, and ⊚ represents a case in which the CV was less than 3%.

TABLE 2 Test No. S2/S1 ESR Adhesion 10 0.1 ⊚ Δ 11 0.2 ◯ ◯ 12 0.3 ◯ ◯ 130.4 ◯ ◯ 14 0.5 Δ ⊚

As can be seen from Table 2, in the case of Test No. 10 in which theratio of the area S2 of the bonding portion to the area S1 of theelectrode layer of the connection portion (S2/S1) is 0.1, ESRcharacteristics are improved but adhesion is deteriorated.

In the case of Test No. 10 in which the ratio of the area S2 of thebonding portion to the area S1 of the electrode layer of the connectionportion (S2/S1) is 0.5, adhesion is improved but ESR characteristics aredeteriorated.

Accordingly, the area of each of the plurality of first and secondisland-shaped adhesive portions 151 and 152 is set to, for example, 20to 40 percent of the area of the first electrode layer 131 a of thefirst connection portion A1 or the area of the second electrode layer132 a of the second connection portion A2. As a result, both improvedadhesion and improve ESR characteristics may be secured.

As described above, a first non-conductive resin layer, extendingbetween a conductive resin layer and an electrode layer of a firstexternal electrode, and a second non-conductive resin layer, extendingbetween a conductive resin layer and an electrode layer of a secondexternal electrode, may be spaced apart from each other to suppress arcdischarge and to improve bending strength.

In addition, a filler may be added to the first and secondnon-conductive resin layers to improve heat resistance.

While embodiments have been shown and described above, it will beapparent to those skilled in the art that modifications and variationscould be made without departing from the scope of the present disclosureas defined by the appended claims.

What is claimed is:
 1. A multilayer electronic component comprising: abody including dielectric layers, and first and second internalelectrodes alternately stacked with respective dielectric layersinterposed therebetween, and having first and second surfaces opposingeach other in a stacking direction, third and fourth surfaces connectedto the first and second surfaces and opposing each other, and fifth andsixth surfaces connected to the first to fourth surfaces and opposingeach other; a first external electrode including a first electrode layerconnected to the first internal electrode and a first conductive resinlayer disposed on the first electrode layer, and having a firstconnection portion disposed on the third surface of the body and a firstband portion extending from the first connection portion along a portionof each of the first, second, fifth, and sixth surfaces; a secondexternal electrode including a second electrode layer connected to thesecond internal electrode and a second conductive resin layer disposedon the second electrode layer, and having a second connection portiondisposed on the fourth surface of the body and a second band portionextending from the second connection portion along a portion of each ofthe first, second, fifth, and sixth surfaces; and a first non-conductiveresin layer and a second non-conductive resin layer disposed on thefirst, second, fifth, and sixth surfaces and spaced apart from eachother, wherein the first non-conductive resin layer extends between thefirst conductive resin layer and the first electrode layer of the firstband portion, and the second non-conductive resin layer extends betweenthe second conductive resin layer and the second electrode layer of thesecond band portion, wherein, when a direction in which the thirdsurface and the fourth surface of the body oppose each other is definedas a length direction of the body, a length of the first conductiveresin layer of the first band portion and a length of the secondconductive resin layer of the second band portion each are 10 to 20percent of a length of the body in the length direction, wherein aplurality of first and second island-shaped adhesive portions aredisposed on the first electrode layer of the first connection portionand the second electrode layer of the second connection portion,respectively, and wherein each of the plurality of first and secondisland-shaped adhesive portions includes a base resin.
 2. The multilayerelectronic component of claim 1, wherein each of the first and secondnon-conductive resin layers includes a base resin, and includes one ormore fillers among a group consisting of silica, alumina, glass, andzirconium dioxide (ZrO2).
 3. The multilayer electronic component ofclaim 1, wherein each of the first and second non-conductive resinlayers includes an epoxy resin and silica, and the content of the silicais 10 volume percent or more.
 4. The multilayer electronic component ofclaim 1, wherein, the first non-conductive resin layer and the secondnon-conductive resin layer are spaced apart from each other in thelength direction with a central portion of the body in the lengthdirection interposed therebetween.
 5. The multilayer electroniccomponent of claim 1, wherein each of the first and second conductiveresin layers includes a conductive metal and a base resin.
 6. Themultilayer electronic component of claim 1, wherein each of the firstand second conductive resin layers includes a plurality of metalparticles, an intermetallic compound, and a base resin.
 7. Themultilayer electronic component of claim 6, wherein the plurality ofmetal particles include at least one of silver (Ag), nickel (Ni), orcopper (Cu), and the intermetallic compound includes at least one ofAg3Sn, Ni3Sn4, Cu6Sn5, or Cu3Sn.
 8. The multilayer electronic componentof claim 1, wherein, when a portion between the first connection portionand the first band portion is defined as a first corner portion and aportion between the second connection portion and the second bandportion is defined as a second corner portion, the first non-conductiveresin layer is disposed to cover the first electrode layer of the firstcorner portion and the second non-conductive resin layer is disposed tocover the second electrode layer of the second corner portion.
 9. Themultilayer electronic component of claim 1, wherein the firstnon-conductive resin layer extends to a portion between the firstconductive resin layer and the first electrode layer of the firstconnection portion, and the second non-conductive resin layer extends toa portion between the second conductive resin layer and the secondelectrode layer of the second connection portion.
 10. The multilayerelectronic component of claim 1, wherein each of the plurality of firstand second island-shaped adhesive portions further includes at least oneof silica, alumina, glass, or zirconium dioxide (ZrO2).
 11. Themultilayer electronic component of claim 1, wherein each of theplurality of first and second island-shaped adhesive portions includes asame material as the first and second non-conductive resin layers. 12.The multilayer electronic component of claim 1, wherein a collectivearea of the plurality of first island-shaped adhesive portions and acollective area of the plurality of second island-shaped adhesiveportions are 20 to 40 percent of an area of the first electrode layer ofthe first connection portion and an area of the second electrode layerof the second connection portion, respectively.
 13. The multilayerelectronic component of claim 1, wherein, in regions of the first andsecond connection portions corresponding to the third and fourthsurfaces of the body, a portion of the first electrode layer is incontact with the first conductive resin layer through an opening of thefirst non-conductive resin layer, and a portion of the second electrodelayer is in contact with the second conductive resin layer through anopening of the second non-conductive resin layer.
 14. A multilayerelectronic component comprising: a body including dielectric layers, andfirst and second internal electrodes alternately stacked with respectivedielectric layers interposed therebetween, and having first and secondsurfaces opposing each other in a stacking direction, third and fourthsurfaces connected to the first and second surfaces and opposing eachother, and fifth and sixth surfaces connected to the first to fourthsurfaces and opposing each other; a first external electrode including afirst electrode layer connected to the first internal electrode and afirst conductive resin layer disposed on the first electrode layer; asecond external electrode including a second electrode layer connectedto the second internal electrode and a second conductive resin layerdisposed on the second electrode layer; and a first non-conductive resinlayer and a second non-conductive resin layer disposed on the first,second, fifth, and sixth surfaces and spaced apart from each other,wherein the first non-conductive resin layer extends between the firstconductive resin layer and the first electrode layer, and the secondnon-conductive resin layer extends between the second conductive resinlayer and the second electrode layer, wherein the first non-conductiveresin layer includes one or more first openings through which a portionof the first electrode layer is exposed to the first conductive resinlayer, and the second non-conductive resin layer includes one or moresecond openings through which a portion of the second electrode layer isexposed to the second conductive resin layer, wherein the one or morefirst openings and the one or more second openings each include aplurality of discrete openings spaced apart from one another, wherein aplurality of first and second island-shaped adhesive portions aredisposed on the first electrode layer of the first external electrodeand the second electrode layer of the second external electrode,respectively, and wherein each of the plurality of first and secondisland-shaped adhesive portions includes a base resin.
 15. Themultilayer electronic component of claim 14, wherein the one or morefirst openings and the one or more second openings are arranged in onlyregions corresponding to the third and fourth surfaces of the body,respectively.